Stories from the Institution of Engineering and Technology

A volume of pamphlets titled, ‘Telescope I’ belonging to the SP Thompson collection was catalogued by the IET Archives in 2015. Even though this volume had been held in the archive collections for many decades, the cataloguing, due to the fragility of the pamphlets, only became possible following conservation work in 2015 (part of a multi-year pamphlet conservation project).

The oldest pamphlet, amongst the mostly 19th century pamphlets, is particularly intriguing. It dates to around 1770 and was written in French by John and Peter Dolland. The title of the pamphlet is ‘description de la lunette achromatique’ or in English, ‘description of the achromatic lens’ and the title page is shown below.

These two individuals, father and son, were involved with one of the oldest chains of retail opticians in the United Kingdom, which was established in 1750, and went on to become known as the opticians Dolland & Aitchison (bought by Boots in 2009 and eventually rebranded).

John and Peter Dolland

Peter Dolland (1731-1820) opened a small optical business in Vine Street, London, on 21 April 1750 and was joined by his father John Dolland in 1752. The Dollands became known for the quality of their optical products and in 1761, John Dolland, now a partner in the business, was appointed optician to King George III and the Duke of York and Albany. Later, in 1820 Peter Dolland and his nephew George Dolland became opticians to George IV.

Peter Dolland worked at first as a silk weaver, but inspired by his father’s passion for optics, he left that profession to set up the optical instruments business. In addition to the optics business Peter is also credited with the invention of the triple achromatic lens, the apochromatic lens in 1763, still in use today, although known as the Cooke triplet, after a later 1893 patent.

The pamphlet ‘description de la lunette achromatique’

The achromatic lens described in the pamphlet is illustrated below.

The time of publication of the pamphlet is not clear as the pamphlet does not include a date. Some sources suggest the publication date was around 1770 and others suggest it was published around 1775.

George Dolland

Peter Dolland’s nephew, George Dolland (1774-1852), together with Peter Barlow, invented an afocal system to extend the focal length of telescopes, called the Barlow lens. He was elected a Fellow of the Royal Society in December 1819 and was one of the founding Fellows of the Royal Astronomical Society.

There are several manuscripts written and signed by George Dolland in the IET Archive collections. These sit amongst a collection of Faraday papers (SC MSS 2) in a file titled ‘committee papers’. The committee referred to was a sub-committee of the Royal Institution that sat in 1828-29 and comprised Faraday, John Herschel (President of the Royal Astronomical Society at that time), and George Dolland. The papers are primarily minutes of the sub-committee meetings and are handwritten by George Dolland. The meeting of 31 December 1829 took place at George Dolland’s house in St Paul’s Church Yard. The minutes of this meeting were signed by George Dolland in his capacity as Chairman and are shown below.

This volume of SP Thompson pamphlets titled, Telescope I’ and the ‘George Dolland sub-committee minutes’ can be consulted at the IET Archive Centre, Savoy Hill House by appointment.